Showing posts with label diagnosis. Show all posts
Showing posts with label diagnosis. Show all posts

Tuesday, October 26, 2010

Doorway diagnosis, but to what end?

Our clinic recently saw an 18-year-old man who had had seizures for most of his life. It seems that they had been well-controlled on a three-times-a-day seizure medication, but his mother had recently tapered it off, and his seizures resumed and did not stop even when she restarted it. One of my Indonesian physician colleagues asked me to join him in the examining room.

The patient had a peculiar facial feature: crowded, shiny papules scattered across his nose and cheeks, as well as some larger, fleshier patches on his forehead. There was another on his lower back. And there was a pale, depigmented patch of skin on his belly. All of these had been there since early childhood.

From this telltale skin features plus his seizure history, it was all but certain that he had a genetic disease called tuberous sclerosis. Most cases arise spontaneously, and indeed there was none in his family, but because of dominant inheritance, each of the patient's own future children will have a 50% chance of inheriting it.

We explained this to him and his mother. She told us she had taken him to specialists in the city since he was little and had never gotten any kind of diagnosis, only a great many expensive and unhelpful tests and therapies. She said the family had sold everything it owned to pay for these trips and consultations.

Though it was gratifying to make that interesting diagnosis in this low-resource setting, the intellectual victory was Pyrrhic. The patient had been hoping for a cure for his seizures and skin problems, and there is no cure for tuberous sclerosis. Still, there's a lot that can be done. If he were lucky enough to be born in the developed world and possessed of good health insurance--or if he were the son of someone very, very rich here--he could have the lesions lasered off, which our textbooks informed us can give excellent cosmetic results. He could consult an experienced pediatric neurosurgeon about possibly removing the growths in his brain which are probably causing his seizures. He could see an eye specialist as well as receive the special education that many TS patients need. He could get a session of genetic counseling, too. With reliable Internet access, he could meet other TS patients online and get a little psychological support.

He has access to none of the above. In fact, he dropped out of school as a child because of his seizures. He is unemployed. His mother told us very frankly that she doesn't think any woman would marry him.  The patient looked miserable to hear all this.

One of my American physician colleagues angrily pointed out to me later that it wouldn't be all that big a deal to at least get the boy's facial lesions lasered off--that alone would make a tremendous difference in his life. That is, it wouldn't be a very big deal if he were in a developed country that allowed for such things.  As it is, though, what we had to offer were adjustments to his seizure medications and a suggestion to see a neurosurgeon who is hundreds of thousands of rupiahs' worth of travel from here.

I'm left wondering what good this diagnosis will be to him and his family. Is there ever a time when one might as well not know?

Monday, November 23, 2009

Strange sheep and their blood

Sometimes the right person spots the right sheep at the right time. It was several years ago in Botswana that Ellen Jo Baron, Ph.D., first laid eyes on the sheep that she now thinks will revolutionize the diagnosis of infectious disease in poor countries.

Baron, an internationally recognized Stanford pathologist, has spent years training lab technicians in the developing world to diagnose infectious diseases. In fact, she literally wrote the book on microbial diagnosis. But she realized it was time to adapt when she discovered one of her densely-worded textbooks locked away and covered in dust in a Malaysian hospital office. She created a low-text, flowchart-rich version of the book for non-English-speaking settings.

Having simplified her textbook, she then had to confront the fact that the photos in it didn't correspond to what her trainees were seeing under their microscopes. The book featured pictures of organisms grown on standard Western lab plates, which are based on sheep- or horse-blood agar. Those animals require too much expensive care and handling to make them available to low-resource labs, which must use human blood instead. Apart from being a biohazard, human blood doesn't behave the same way that animal blood does in diagnostic tests--so the labs that use it couldn't make sense of the photos in her textbook.

Then came her trip to Botswana, where she saw one of these. "'What is that?'" she recalls asking herself. "Clearly, it wasn't a goat and it wasn't a sheep--it was some other thing." It was a hair sheep, a cousin of the familiar wool sheep that has some unsheeplike traits. It is happy in hot climates and small pastures, resistant to parasites and other infections, and, of course, needs no shearing. Such a low-maintenance animal, Baron realized, could be a big boon to labs in the developing world. After finding a rare herd of wool sheep at an experimental farm in California and convincing the owners to let her tap the sheeps' jugulars, Baron tried the standard microbial diagnostic tests on hair sheep blood, at her own expense. All the tests worked beautifully. The blood produces standard results without the need for expensive techniques or unaffordable animals.

Clinical laboratories are unsung and unglamorous places, but they are in many ways the brains of the hospital--or at least the left hemisphere to the physician's right. Microscopes and centrifuges and other analytic equipment allow for the types of decision-making--about patients' health, about germs and their drug susceptibilities, about genes even--that revolutionized 20th-century medicine. Yet few American doctors visit their hospital's lab or know the name of its director. Few of us have looked down a microscope or counted colonies since those squirmy afternoon sessions in medical school, and that leaves us both unprepared to diagnose malaria or anemia singlehandedly and unappreciative of the equipment and supplies and expertise that are needed to make that diagnosis. In short, we seldom think about how central the laboratory is to any medical effort. Photogenic medical missions to fix cleft lips and congenital heart defects are sorely needed, but so are the bent backs of the microscopists--perhaps more so.

Hearing of Baron's discovery, people have begun to come out of the woodwork, wanting to help. An American hair sheep breeders' association is interested in sending sheep to Southeast Asia and training people in their simple husbandry. A Brazilian blood distribution company has offered a citrated blood-storage bag. And one Botswanan lab is beginning to use hair sheep already. All Baron needs is the time and money to put the hair sheep where they're needed. She's determined to do it. As she told a Stanford interviewer last fall, getting hair sheep to labs in the developing world "is going to change everything."